Fiat will be around for a longgg time. It takes decades at least to faze it out. And old people are still used to it.
Old people are slowly disappearing though. But yeah, it will probably take a while. I'm wondering which countries will be the first to get rid of fiat though. Developed countries seem like they are in the best position to move towards electronic cash systems. But at the same time, undeveloped countries could benefit from just going digital straight away, instead of investing heavily in physical cash creation and security features.